20204-71-1Relevant academic research and scientific papers
Palladium-catalyzed cross-coupling of benzyltitanium(IV) reagents with aryl fluorides
Li, Yan
, (2022/01/11)
The first palladium-catalyzed cross-coupling between benzyltitanium(IV) reagents with aryl fluorides is reported. A variety of diarylmethanes can be prepared in good to excellent yields by the catalyst system of PdCl2(dppf)2 associated with 1-[2-(di-tert-butylphosphanyl)phenyl]-4-methoxypiperidine. This reaction offered a highly efficient approach to diarylmethanes that are commonly found in life-changing drug molecules. Graphical abstract: [Figure not available: see fulltext.]
Mixed Alkyl/Aryl Diphos Ligands for Iron-Catalyzed Negishi and Kumada Cross Coupling Towards the Synthesis of Diarylmethane
Ma, Xufeng,Wang, Han,Liu, Yao,Zhao, Xing,Zhang, Jun
, p. 5134 - 5140 (2021/11/16)
Mixed alkyl/aryl diphos ligands have been prepared and their application in iron-catalyzed cross coupling of benzylic chlorides with diaryl zinc (Negishi) or aryl Grignard reagents (Kumada) towards the synthesis of diarylmethane has been evaluated. The iron?diphos catalytic system exhibited the enhanced activity and selectivity in the two coupling reactions. The electron-rich mixed PPh2/PCy2 ligands outperformed their symmetrical PPh2 congeners, and led to decreased homocoupling byproduct formation. It indicates that the electronic effect of the ligands plays an important role in the catalytic performance. The Fe catalyst supported by L8 bearing an electron-rich PCy2 substituent and a sterically demanding tert-butyl on ethene backbone exhibited the best catalytic performance and good functional group tolerance in the two cross coupling reactions.
Heteroleptic Ni(II) Complexes Bearing a Bulky Yet Flexible IBiox-6 Ligand: Improved Selectivity in Cross-Electrophile Coupling of Benzyl Chlorides with Aryl Chlorides/Fluorides
Shen, Zheng-Wang,Meng, Die-Die,Imran, Sajid,Yan, Chun-Hui,Sun, Hong-Mei
supporting information, p. 3540 - 3545 (2020/10/09)
A bisoxazoline-derived NHC known as IBiox-6 reacted smoothly with Ni[P(OEt)3]2Br2 and Ni(PPh3)2Br2 to give the respective heteroleptic Ni(II) complexes Ni(IBiox-6)[P(OEt)3]Br2 (1) and Ni(IBiox-6)(PPh3)Br2 (2) in yields of 60% and 71%. Their crystal structures were characterized to reveal a rare cis disposition of the IBiox-6 ligand to the phosphite ligand in 1, while 2 possessed the more common trans configuration. Both complexes catalyzed the cross-electrophile coupling of benzyl chlorides with aryl chlorides and fluorides in the presence of Mg turnings at 50 °C via a "real one-pot"procedure, featuring no requirement for temperature variation or portionwise addition of any coupling partner. In particular, complex 1 showed a better balance between the catalytic activity and selectivity. The scope of the procedure catalyzed by 1 and Mg turnings was investigated, providing a highly selective, simple, and practical approach to the synthesis of diarylmethanes with high steric hindrance and various functional groups, including oligo-diarylmethane with asymmetric structures.
Preparation and application of blended nickel (II) complex with bisoxazoline derived azacyclo-carbene ligand and phosphite ester ligand
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Paragraph 0079-0080, (2019/10/17)
The invention discloses a blended nickel (II) complex with a bisoxazoline derived azacyclo-carbene ligand and a phosphite ester ligand and application of the blended nickel (II) complex. The blended nickel (II) complex has a chemical formula of Ni(NHC)[P(OR)3]X2, in the formula, R is one of ethyl or isopropyl; X is one of bromine atoms or helium atoms; and NHC is the bisoxazoline derived azacyclo-carbene ligand. In the presence of magnesium chips, the blended nickel (II) complex with the bisoxazoline derived azacyclo-carbene ligand and the phosphite ester ligand, which is disclosed by the invention, is capable of catalyzing aromatic hydrocarbon or fluoro-aromatic hydrocarbon with low activity to have a reduction cross coupling reaction with a benzyl chloride type compound at a single temperature, then a diarylmethane compound can be generated at one step, and a novel method is provided for synthesizing diarylmethane compounds.
Gold(I)-catalyzed Benzylation of (Hetero)aryl Boronic Acids with (Hetero)benzyl Bromides by the Strategy of a SN2-type Reaction
Zang, Wenqing,Wei, Yin,Shi, Min
supporting information, p. 2791 - 2795 (2018/09/20)
Herein, the first example of gold-catalyzed benzylation of (hetero)aryl boronic acids with (hetero)benzyl bromides to give the corresponding cross-coupling products in moderate to good yields is reported. The reaction proceeds through a possible intermolecular SN2-type reaction pathway to give a wide variety of di(hetero)arylmethanes as the desired products. An intriguing reaction mechanism has been proposed on the basis of control experiments, 31P-NMR spectroscopic detection and DFT calculations.
Efficient N-heterocyclic carbene nickel pincer complexes catalyzed cross coupling of benzylic ammonium salts with boronic acids
Liu, Xi-Yu,Zhu, Hai-Bo,Shen, Ya-Jing,Jiang, Jian,Tu, Tao
, p. 350 - 353 (2017/01/28)
Pyridine-bridged bis-benzimidazolylidene nickel complexes exhibited very high catalytic activity toward cross coupling of inactive (hetero)aryl benzylic ammonium salts with (hetero)aryl and alkenyl boronic acids under mild reaction conditions. Even at 2 mol% catalyst loading, a wide range of substrates for both coupling partners with different steric and electronic properties were well tolerated.
Synthetic method of diarylmethanes
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Paragraph 0066; 0067; 0068; 0069; 0070, (2017/08/28)
The invention discloses a synthetic method of diarylmethanes. The method is characterized in that benzyl pseudohalide and aromatic boric acid are reacted in an organic solvent under alkaline condition. The method employs easily available raw materials, conversion is realized under effect of no transition metal catalysis, water-free and oxygen-free are not required, Lewis acid catalysis is not required, the method has wide substrate universality, and various substituted diarylmethanes can be synthesized by the method.
One-pot reductive coupling reactions of acetyl naphthalene derivatives, tosylhydrazide, with arylboronic acids
Shen, Xu,Liu, Ping,Liu, Yang,Liu, Yan,Dai, Bin
supporting information, p. 785 - 793 (2017/01/16)
In this study, a one-pot two-step reductive coupling between acetyl naphthalene derivatives, tosylhydrazide, and arylboronic acids, affording substituted 1(or 2)-(1-phenylethyl)naphthalenes in moderate-to-excellent yields, was reported. Notably, solvent played a crucial role in the coupling of 1-acetyl naphthalene derivatives (toluene) or 2-acetyl naphthalene derivatives (1,4-dioxane) as starting materials. Meanwhile, the scope of this one-pot coupling reaction was extended to 1(or 2)-naphthaldehyde substrates. Particularly, the system was also suitable to synthesize 1(or 2)-(1-phenylethyl)naphthalenes on a multi-gram scale, and was applied in the synthesis of naphthylmethyl substituted carbazolyl compounds.
Coupling of arylboronic acids with benzyl halides or mesylates without adding transition metal catalysts
Wu, Guojiao,Xu, Shuai,Deng, Yifan,Wu, Chaoqiang,Zhao, Xia,Ji, Wenzhi,Zhang, Yan,Wang, Jianbo
, p. 8022 - 8030 (2016/11/19)
We report herein a transition-metal-free coupling reaction of arylboronic acids with benzyl halides and mesylates for the construction of C(sp2)[sbnd]C(sp3) bonds. A unique feature of this coupling reaction is the formation regioisomers in some cases. Mechanistic studies suggest that this reaction may proceed via an unprecedented Friedel–Crafts-type reaction pathway under base conditions with the assistance of boronic acid moiety.
Superacid BF3-H2O promoted benzylation of arenes with benzyl alcohols and acetates initiated by trace water
Zhang, Shuting,Zhang, Xiaohui,Ling, Xuege,He, Chao,Huang, Ruofeng,Pan, Jing,Li, Jiaqiang,Xiong, Yan
, p. 30768 - 30774 (2014/08/05)
A convenient procedure employing simple starting materials benzyl alcohols and acetates as the benzyl donors to assemble a series of diarylalkanes through benzylation of arenes using in situ prepared superacid BF3-H 2O as an efficient promoter has been developed. The beneficial role of water in the reaction has been clarified with combination of control experiments and 11B NMR analysis. This reaction is a self-promoted model, which is triggered by the trace of water and continuously promoted by self released by-product water (or carboxylic acid). A wide range of substrates are investigated and the moderate to excellent yields and the good regioselectivities for secondary benzyl alcohols as well as arenes bearing electron-withdrawing groups have been achieved. As a result, moisture in the reaction system has been utilized as an efficient initiator in all benzylation cases.
